Virtual destructors should have virtual keyword.

content/common/font_config_ipc_linux.h

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_COMMON_FONT_CONFIG_IPC_LINUX_H_
 #define CONTENT_COMMON_FONT_CONFIG_IPC_LINUX_H_
 #pragma once
 
 #include "skia/ext/SkFontHost_fontconfig_impl.h"
 
 #include <string>
 
 // FontConfig implementation for Skia that proxies out of process to get out
 // of the sandbox. See http://code.google.com/p/chromium/wiki/LinuxSandboxIPC
 class FontConfigIPC : public FontConfigInterface {
  public:
   explicit FontConfigIPC(int fd);
-  ~FontConfigIPC();
+  virtual ~FontConfigIPC();
 
   // FontConfigInterface implementation.
   virtual bool Match(std::string* result_family,
                      unsigned* result_filefaceid,
                      bool filefaceid_valid,
                      unsigned filefaceid,
                      const std::string& family,
                      const void* characters,
                      size_t characters_bytes,
                      bool* is_bold, bool* is_italic);
   virtual int Open(unsigned filefaceid);
 
   enum Method {
     METHOD_MATCH = 0,
     METHOD_OPEN = 1,
   };
 
  private:
   const int fd_;
 };
 
 #endif  // CONTENT_COMMON_FONT_CONFIG_IPC_LINUX_H_